Automatic clutch



May 1937- E. v. .1. TOWER 2,079,753

AUTOMATIC CLUTCH Filed Dec. 20, 1934 s Sheets-Sheet 1 INVENTOR. EAME'E.KJ 70/4 58 ATTORNEY.

y 1937- I E. v. J. TOWER 2,079,753

AUTOMATIC CLUTCH Filed Dec. 20, 1934 3 Sheets-Sheet 2 r v F/g Z? ,w Tl iiiiyll i INVENTOR.

ATTORNEY.

y 1937- E. v. J. TOWER 2,079,753

AUTOMATIC CLUTCH Filed Dec. 20, 1934 3'Sheets-Sheet s ea V.

INVENTOR.

az/mse' K J ran/5e ATTORNEY.

Patented May 11, 1937 UNITED. STATES PATENT OFFICE AUTOMATIC CLUTCH Application December 20, 1934, Serial No. 758,465

13 Claims.

a clutch-pedal is provided whereby the depressingof the pedal will disengage the clutch members even though they have been engaged by the automatic means-thus enabling the usual gear-shifting operation to be made.

The converter mechanism referred to is intended to provide for certain conditions wherein it is desirable to convert the clutch into the conventional type with the driving and driven members positively engaged instead of disengaged. Such a condition is necessary when the engine is at rest and it is desired to spin the motor over by pushing or towing the car with the transmission gears in mesh; or in cases where it is desired to park the car with the gears in mesh as a further braking means for safety reasons.

In the present improvements, this conversion is accomplished through the operation of the ordinary clutch pedal and new. associated devices. The pedal has its usual retracting spring for restoring the pedal to normal or rest position. When the pedal is depressed (as in the ordinary clutch-disengaging operation) the retracting spring may be connected through the converter mechanism with the clutch levers. Upon release of the foot pedal the retracting spring pulls the clutch members progressively into engagement bearing plate withparts broken away to show the interior thereof;

against the tension of their disengaging springs. I

Figure III is a sectional view .of the release roller taken on substantially the line III-III of Figure I and showingthe position of the release fork with respect to the release collar;

Figure IV is a sectional view of the release collar taken on substantially the line IV--IV of Figure III; I

Figure V is an enlarged side view partly in section of the converter mechanism and release collar of Figure I;

Figure VI is a partial side view of the sleeve housing shown in Figure V upon which the release collar is mounted;

Figure VII is an end view of the structure shown in Figure VI;

Figure VIII is a partial sectional view on a reduced scale showing the relation of the release fork shaft and release fork to the release collar illustrated in Figure III; and

Figure IX is a more or less diagrammatic illustration of the clutch pedal assembly associated with the release fork shaft 81.

Automatic clutch The automatic clutch mechanism, which is also described in the copending application above referred to, is constructed as follows:-

- a A mounting cover I is secured by cap screws II 'to a major driving member I2 which is here shown as the fly wheel of a motor vehicle. The driving member I2 is rotated in the usual manner during the operation of the motor vehicle. Between the cover Ill and the fly wheel I2 is positioned a driven member l3 splined to one end of the transmission jack shaft M. The other end of the jack shaft is connected to and part of a conventional transmission not here shown. The driven member l3 may be of any conventional form and is provided with the usual friction mats l5 adjacent its periphery, and a vibration dampener assembly when required. I

A pressure plate I 6 which may be formed of cast metal is positioned concentrically between the driven member I3 and the cover 10. It is connected to the mounting cover and rotates therewith. The connection between the pressure plate pression springs 2d positioned on the outside of the cover It.

The cover if] is provided with a plurality of circular depressions 2i, each having a central opening -t-herethrough. A release and tension and adjusting stud 22 is attached to the pressure plate it by screw-threaded connection therewith and extends through the central openings in each of the depressions 2i. An adjusting cap 23 is secured to the outer threadedentremity of each of the studs 22. The springs iii are compressed between the bottom of the depressions 2i and the adjusting caps 23 to maintain the pressure plate i6 out of engagement with the friction surface of the driven member it, whenever the driving member if is at rest or is rotating at normal motor idling speeds.

The mechanism thus far described includes a driving member in the form of a fly wheel if, a driven member iii having a peripheral friction surface 55, and a pressure plate 86 loosely connected to a mounting cover iii which rotates with the fly wheel i2. The driven member 93 when at rest normally floats between the fly wheel i2 and the pressure plate in and out of engagement with both of these members. This is made possible by reason of the compression springs 20 which normally hold the pressure plate 66 away from the friction surface it of the driven member l3. Thus at normal idling speeds, the slow rotary movement of the fly wheel t2, the cover iii and the pressure plate l6 slidably associated therewith, is not transmitted to the driven membet it. However, when the pressure plate is actuated, as will be described hereinafter, to press against the friction surface it of the driven member it that member is progressively and securely compressed between the pressure plate 56 and the fly wheel l2 and rotates with these members until idling speeds again obtain unless declutched for the free wheeling function. The rotary movement of the friction member is thus transmitted through the shaft it to the conventional transmission and drive shaft assemblies, and finally to the driving wheels of the vehicle.

The centrifugal weight mechanism for automatically engaging the clutch members is as follows:

The weights 2% (Fig. I) are mounted to oscillate upon tubular pins as, and to actuate (through the interposed springs 3i) levers 33. There are a plurality of these weights located concentrically around the cover it of the clutch unit in the usual manner.

When the cover it is rotated by reason of its connection with the flywheel if the weights 2B swing radially outwardly about the pins 2Q causing the cam surfaces 633 on the levers 33 to press the thrust pins 39 against the pressure plate it. The friction surface it of the driven member i3 is thereby brought into engagement progressively with both the flywheel i2 and the pressure plate it.

These parts are described more in detail in the said copending application.

In order to limit the outward movement of the weights 28 these weights are provided with arms 34 at their radial outermost extremity; and these arms come to a stop position against adjustable non-metallic stops consisting of a. plurality of strips 40 secured to the cover l0. These strips are held in position by means of a. screw M extending through the strips and threaded into the cover 10. A sufficient number of strips $0 are aovavas used to limit the pivotal movement of the weights 28 to the desired extent.

Within the weights 28 are recesses 35 adapted to receive compression springs 37. Each lever 33 is provided with a pressure pad 42 at its extremity adjacent the springs 37, and at the inner end the levers are formed with a pressure pad 36, adapted for use in manually controlling oidtch operation independently of the Weights as later described. Between the pad (l2 and the springs 37 is a release bar (it which is held in contact with the pad 52 at all times by means of the preloaded springs 371.

When the weights 28 swing outwardly under centrifugal action due to the rotation of the clutch members, the weights act through the springs 37 and release bar l? and pad 12 to oscillate the levers and cause the cam surfaces 33 thereof to press the pressure pins 39 against the pressure plate iii to engage the clutch as already referred to.

The springs 37 are preloaded into place under initial compression, so that the release bars (it are pressed against the lever pads 52 at all times. The preloaded action of the springs 31 serves to hold the intermediate pressure pad '36 (midway down the long arm of the lever 33) against the weight 28. After the weights have moved outwardly sufiicient to engage the clutch by the above described operation, a further movement of the weights 28 takes place under increased rotating speeds, thus permitting the weights to move an additional predetermined distance until the stop arms 341 reach the stops ill. This eifects a slight separation between the weight 23 and the pad 66 on lever 33, thereby slightly increasing the compression of the springs 37, and also increasing the lateral pressure of the pins 35! against the pressure plate it. This increased lateral pressure serves to prevent slippage during suddenly increased torque loads imposed upon the clutch, such as starting in intermediate or high gear.

Clutch pedal disengagement Such being the operation of the automatic devices for effecting clutch engagement from variable speeds of rotation of the clutch, there is provided in addition the usual pedal control for disengaging the clutch members (that is, the

driving and'the driven members) for all operating purposes, such as shifting gears, stopping and starting, etc., regardless of the rotating speed of the clutch.

A release collar 53 (Fig. I) is slidably mounted upon a cylindrical sleeve housing 56 enclosing the shaft it. The collar 53 is provided with two bearings 55 (see Figs. III and IV) which are engaged by a release fork connected with the clutch pedal as presently to be described. At the inner end of the collar 53 is attached one race of a ball bearing 56 having an annular groove 5?. A detachable race portion 58, similar to 56, and also having an annular groove, provides the other race for the balls 59. These parts of the bearing are held in position by cage 69. The outer surface of the portion 58 engages the above mentioned pads Mon the release levers 33.

When the clutch pedal is depressed as later to be described, and its release fork presses to the left in Fig. I, this bears against two of the opposed contact surfaces 55 of the release collar 53 which action slides the collar along the housing 54 thus pressing the member 58 against the lever pads Ml. This pressure oscillates the levers studs ll (see Figs. I and II).

33 about their pins 29, thus moving the cam surfaces 43 to the right in Fig. I and releasing the pressure of the pins 33 against the pressure plate Hi. This permits the springs 23 to retract the pressure plate It, thus disengaging the clutch.

In this pedal action just referred to, the oscillation of the levers 33 as just described, results in further compressing the springs 31; and when the weights 23 have moved outwardly sufliciently to bring the arms 33 against their stops, the release pedal pressure for declutching never has a greater force to overcome than to compress the springs 31 from this position. In this manner it is possible to effect easy declutching without overcoming the forces resulting from the energization of the weights 28 which of course become progressively greater at high motor speeds.

Converter mechanism The operation of the converter mechanism for converting the automatic clutch into a conventional type of clutch will now be described.

Surrounding the shaft l4 and slidable laterally thereon, is a converter skeleton sleeve and bearing ring plate assembly 10 which has projecting laterally from it three equi-spaced parallel These studs rest or slide in registering semi-circular grooves 12 (see Figs. VI and VII) formed part in the sleeve housing 54 and part in the release collar 53, as also shown in Figs. III and V.

The converter bearing ring plate ID at its bearing surface is caused to 'bear upon auxiliary lever pads '53 extending from the lower ends of the levers 33. The bearing plate I is made up of two rings separated bya series of ball bearings M as indicated in Fig. II so as to provide non-frictional contact when brought into engagement with the auxiliary lever pads 13. The movement of the bearing plate 10 (to the left in Fig. I) is limited by a spring stop projection 8! carried by the housing 53 (Fig. VI) by reason of the engagement thereof with notches 82 formedin one of the studs. ll. Thus, upon depressing the clutch pedal, registration of the stud notches I and interlocker latch ring I5 (referred to below is assured.

These notches 15 are formed in the studs H (see Figs. II and V) and are arranged to be engaged simultaneously by an interlocker ring 16 which is shown in Fig. III. The ring 16 is mounted to turn slidably upon the collar 53. The turning movement thereof is limited by the slots H and screws it which secure and pilot the interlocker ring it to the collar 53.

An integral arm 73 extends outward from the interlocker ring it, to which arm is attached a swivel block for securing a Bowden wire, per standard practice, indicated at 83 in Fig. V. The button control of this Bowden wire may be extended to any convenient location for use by the operator for moving the latching ring 13 either into its latched or its unlatched position as desired. i

The ring 13 is formed with certain cutaway portions 15a which normally permit the notched studs H to slide therethrough. But when the notches 1501 the studs are longitudinally in register with the interlocking latch ring 16, then the ring may be partially rotated by means of the Bowden control button (counter clockwise in Fig. III) and this will bring the solid portions of the ring 13 into the notches 15 so asthus to interlock the ring and the notched studs together in a slidable tandem assembly.

Since this ring 16 is mounted upon the collar 53, then movement of the copar 53 (under the control of the clutch pedal as above explained) will carry the interlocker ring 16 along with it in its movements along the sleeve 54 in either direction. The parts are so arranged that the interlocker ring 16 will arrive at a point to register with the notches 15 when the release collar 53 is moved to the left (Fig. I) by the action of the clutch pedal.

While the clutch pedal is inthis depressed position the interlocker ring 16 may be shifted to engage the notches 15 in studs 1| through means of the Bowden wirelll). When this engagement has been effected and the clutch pedal permitted to return to its normal position the ring I6 pulls the studs II and the attached bearing plate to the right in Figure I causing the bearing to press upon the pads 13 at the inner ends of the levers 33. In this manner the levers 33 may be actuated manually to duplicate the action effected automatically by the weights 28 and associated parts. -When the levers 33 are thus actuated.

manually the mechanical'advantage of the levers is substantially increased due to the increased ratio between the pads 13 and thepivot pins 29.

In converting the clutch from automatic to conventional form, the action of the clutch is reversed. It will be recalled that when the clutch is under its automatic operation the driven meming member 02 and the pressure plate l6. This is due .to the effect of the springs 20. When the converter mechanism has been interlocked, the driven member I3 is normally held in contact with the driving member J2 and the pressure plate l6 by reason of the pressure of bearing plate 10 upon levers 33. To disengage the clutch when the converter mechanism is interlocked it is necessary to depress the clutch pedal thereby moving bearing plate 10 to the left -.(Fig-:I) and permitting springs 20 to pull pressure plate [6 away from the driven member l3.

To reconvert the clutch to its automatic form it is merely necessary to shift the interlocker ring 16 so that the notches a. in the edge thereof are brought into alignment with the studs H. This may be accomplished by a movement of the Bowden wire 80 while the clutch pedal is depressed and the collar 53 and associated parts are at the extreme left position (Fig. I). When the interlocker ring '73 has thus been shifted back to its inoperative position the bearing plate 10 is disengaged from the collar 53 and the release of the clutch pedal (movement of the collar 53 to the right) again places the pressure plate It under the influence of the springs 20.

During the conversion operation to conventional, it will be understood that the retracting spring for restoring the clutch pedal to normal position, must be strong enough to overcome the tension of the clutch disengaging springs 20; and to finally positively engage the clutch against slip.

Clutch pedal and connections for converter The clutch pedal and connections will now be described with reference to Figs. I, III and IX.

A clutch pedal 85 of conventional design is connected to a release fork shaft 81 through suitable linkage and adjusting means. Shaft 31 is provided with two forks 83 each of which carry a roller 89 adapted to engage the bearings 55 formed in collar 53.

In Figure IX the clutch pedal 85 is shown in its normal or retracted position. When it is ber I3 is normally'out of contact with the drivdepressed or moved toward the left, the shaft 81 is rotated in a counter clockwise direction causing the forks 88 to press the collar 53 to the left (Fig. I). As previously described when the collar 53 is moved to the left the interlocker ring i6 is brought into registry with the notches E5 in the studs H and may be shifted by the wire 80 to effect an engagement between the studs and the interlocker ring.

Upon releasing the clutch pedal 85, it is restored to its retracted or normal position by retracting spring 90. The eifective force of spring 90 upon shaft 81 is sufficient to move the collar 53, hearing plate l8 and levers 33 to the right (Fig. I) and overcome the force of springs 20, thereby causing a positive engagement of the clutch. When pedal 85 is depressed a counterclockwise rotation is imparted to shaft 81 through the adjustable lever arm 85. When pedal 85 is released spring 98 imparts a clockwise rotation to shaft 81 through means of the link toggles 9i and 92 and adjustable lever arm 93.

Link 9! is pivotally connected to a stationary bracket am at one extremity and pivotally connected to link 92 at its other extremity. Link 92 is pivotally connected to adjustable lever arm 93. One end of spring 98 is connected to links 9! and 92 at their junction point as shown in Figure IX. The other end of the spring is connected to a stationary bracket 98a. The link 9! is somewhat shorter than link 92 and thetwo links are so arranged that they cannot be pulled downwardly past center by spring 90.

The pedal retracting and converter engaging function is accomplished primarily through the coaction of the link toggles 9i and 92 and retracting spring 90 which together control the amount of pull that can be exerted at the clutch levers 33. By reason of the arrangement of these parts a low pedal pressure is obtained while at the same time an adequate pressure is provided for effectively engaging the clutch when the converter ring is in its interlocked position.

These advantages are made possible by reason of the unequal length of the link toggles. 9i and 92 together'with the angle .of inclination of the links. When the pedal is depressed the inclination of the shorter link 9| is such that the in-- creased tension of retracting spring 98 is in efiect temporarily canceled, thus avoiding an excessive resistance to the movement of pedal 85. On the other hand, when the pedal 85 is released the efiect of spring 98 is applied to shaft 81 through link 9|, 92 and 93 and progressively increases as these approach their normal position as illustrated in Figure IX.

, Rsum From the foregoing description it will be apparent that the clutch assembly embodying the present invention maybe readily converted from automatic to manual (conventional) operation and reconverted from manual to automatic operation.

During automatic operation the driving and driven members are normally held in disengaged relation by the springs 20. Levers 33 are operated upon by weights 28, under the influence of the rotary movement of the clutch, to efiect engagement of the driving and driven members. Disengagementmay be effected either by reducing the motor speed to such an extent that the force of springs 28 overcomes the centrifugal force of weights 28; or by depressing the foot pedal 85 and, thereby pressing collar 53 against levers 33 to rotate the latter in a clockwise direction against the force of springs 31.

The clutch may be converted from automatic to manual operation by depressing the pedal 85 whereby to move release collar 53 to the left (Fig. I). At its extreme left position the inter-- locker ring i5 carried by collar 53 registers with notches in converted bearing plate studs H. While in this position the ring 75 may be rotated to enter notches 15 by pulling the Bowden wire 80.

The converter bearing plate 18 is then interlocked with and in eifect made a part of collar 53. Upon releasing pedal 85, retracting spring .98 restores the pedal to its inoperative position and moves collar 53 and converter bearing plate 15 to the right (Fig. I) thereby rotating levers 33 in a counterclockwise direction against the force of springs 28 causing pressure plate it to engage the driven member 13 and press it against driving member l2. While the converter bearing plate i0 is interlocked with the collar 53, the driving and driven members are normally held in engaged position and can be disengaged only by depressing pedal 55.

The clutch may be reconverted to automatic operation by depressing pedal 85 to move converter bearing plate 18 to its extreme left position (Fig. I) and then rotating interlocker ring it by pushing wire 80 to bring notches 15 into alignment with studs li. Upon releasing the foot pedal, the collar 53 is moved to the right (Fig. I) into its inoperative position by spring 90 while converter bearing plate 15 remains at its extreme left position. The spring 8! in sleeve 55 engages one of the notches 82 in stud ll thereby properly positioning bearing plate 10 when it is detached from collar 53. Several notches 82 are formed in stud H in order to compensate for wear in the associated operating parts and thereby insure proper positioning of bearing plate 18 regardless of such wear.

. The scope of the invention is indicated in the appended claims.

1. In a clutch, a driving member, a driven member, levers arranged to effect engagement and disengagement of said members, a release collar adapted to operate upon said levers to effect disengagement only of said members, a retracting spring yieldably holding said collar in its inoperative retracted position, converter mechanism adapted to engage said levers, and means for interlocking said converter mechanism with said collar whereby said retracting spring 7 may be employed to efiect engagement of said driving and driven members.

2. In a clutch, a driving member, a driven member, levers arranged to eflect engagement and disengagement of said members, a release collar adapted to operate upon said levers to effect disengagement only of said members, converter mechanism adapted to operate upon said levers to eflect engagement of said members when interlocked with said collar, and means for manwhen interlocked with the collar, and manual means for interlocking said converter with' said collar.

4. Converter mechanism for an automatic clutch comprising a converter assembly slidably mounted upon a bearing sleeve, said assembly including a plurality of notched studs arranged longitudinally of said sleeve, a release collar slidably mounted upon said sleeve, an interlocker ring carried by said collar, and means for causing portions of said ring to enter the notches in the said studs whereby to effect an interlock between the converter assembly and the collar.

5. Converter mechanism for an automatic clutch comprising a converter assembly slidably mounted upon a bearing sleeve, a release collar slidably mounted upon said bearing sleeveindependently of said converter assembly, a retracting spring yieldably holding said collar in its retracted position away from said converter, manually operated means for projecting said collar against the resistance of said spring to its extended position toward said converter, and means for interlocking said converter assembly with said collar only while the latter is in its extended position.

6. Mechanism of the character described in claim wherein the interlocking means comprises a latching ring carried by the collar adapted to engage a recess formed in a portion of the converter assembly.

7. Mechanism of the character defined in claim 5 wherein the converter assembly includes a plurality of notched studs and wherein the collar is provided with a latching ring adapted to engage the notches in said studs.

8. Mechanism of the character defined in claim 5 wherein means is provided for yieldably holding the converter assembly in a predetermined inoperative position on said bearing sleeve.

9. Mechanismof the character defined in claim 5 wherein the interlocking means comprises a latching ring carried bythe collar adapted to engage notches formed in a portion of the converter assembly and manually operated means for effecting an interlock between said latching ring and said notches.

10. In a clutch, a driving member, a driven member, release mechanism adapted to operate upon said driving member through intermediate means to effect disengagement only of said members, converter mechanism adapted to operate upon the driving member through the same intermediate means toeffect engagement only of said members, said' converter mechanism being operable only when interlocked with said release mechanism, and means for interlocking the converter and release mechanism.

11. In a clutch, a driving member, a driven member, release mechanism adapted to operate upon the driving member to effect disengagement only of said members, said release mechanism including a retracting spring yieldably holding the mechanism in its inoperative position, a converter assembly adapted to operate upon the driving member to efiect engagement of the members only when interlocked with the release mechanism, and means for interlocking the converter assembly with the release mechanism.

12. In an automatic clutch, including driving and driven members, converter mechanism comprising a release collar for effecting engagement of the clutch slidably mounted upon a bearing sleeve, a converter assembly for effecting engagement of the clutch when interlocked with the collar also slidably mounted upon said sleeve independently of said collar, and means for interlocking said converter assembly with said collar.

13. In a clutch, a driving member, a driven member, levers arranged to efiect engagement and. disengagement of said members, a release collar adapted to operate upon said levers to eifect disengagement only of said members, and means detachably connected to the collar adapted to operate upon said levers to efiect engagement only of said members.

ELMER V. J. TOWER. 

